Newlands Cross Upgrade EIS - European Investment Bank

South Dublin County Council N7 Newlands Cross Upgrade
Environmental Impact Statement
Arup Consulting Engineers
3.11.12.3 Impact of the proposed development Option 2 (Underpass)
This option consists of a tunnel at a maximum of 9 metres below existing ground levels and
accessed by two ramps into the ground in and east-west axis along the existing N7 route (see
Figures 3.6, 3.9 and 3.10).
The following visual elements will form part of the completed underpass:
• Selected precast facing panels to the sides of retaining structures along the sides of
approach ramps.
• Galvanised steel crash barriers 1.25 metres high to the sides of the Fonthill / Belgard
roadway (R113) above the proposed tunnel.
• Lighting columns (not designed to date) will be located along the edge of the roadway.
• Typical motorway / NRA road signage at the required locations along the road corridor.
• A new two metre high wall along the northern boundary of Newlands Golf Course with
tree planting behind to replace the tree planting removed during construction.
• A new two-metre high stone wall along the boundary of the agricultural land to the south
east with new tree planting behind.
The visual impact of this option will be slight and positive, there will be no significant
elements above the existing ground level and views into the openings for the ramps will be
extremely localised and will not be visible from surrounding areas.
Similar to Option 1 the development will greatly improve traffic flow at the junction reducing
the visual clutter caused by traffic stopped at the junction on a daily basis.
3.11.12.4 Mitigation Measures ( Operational Phase )
Reduction of visual impact of the proposed options will be achieved by the following
methods:
1. The elevational treatment of the retaining structures – selection of materials and colours to
compliment the surrounding built environment.
2. Insertion of a high quality landscape design as visual buffering to include a planted
mound along the northern boundary of the golf course (mound to be part of Option 1
mitigation measures only).
3. Retention, where possible, of the existing tree planting on or adjacent to the site.
4. Consistency in the appearance of the selected materials along the road corridor – road
signage, lighting, barriers etc.
5. Reinstatement and repair of any damaged footpath / road surfaces, boundaries etc.
6. Through the design of the acoustic barrier, if required, along the road edge to incorporate
a high quality finish on elevation.
3.11.13 Summary
The primary significant and negative visual impacts will be during the construction phase and
will be short term – ceasing, in the worst case, three years after construction commences.
However on completion of the works and with the establishment of the proposed planting, the
visual impact will be generally moderate and neutral, with the exception of the localised
moderate and negative visual impact to the rear of the houses backing on to the N7, in the case
of option 1 (the overpass) and slight and positive in the case of option 2 (the underpass). Both
options will be seen as a natural improvement to the existing road system, improving traffic
December 2007 Page 49